A centrifugal solidification integrated device and method for manufacturing functionally graded material insulators

Abstract

The application provides a centrifugal solidification integrated device and method for preparing a functionally graded material insulator, and comprises: a sealed heating cabin including a cabin body, a heat insulation shell and a heat preservation heating layer laid on the inner wall of the heat insulation shell, which is used for providing a heating environment; a magnetic coupling centrifugal driving system including a rotating table arranged in the cabin body and a magnetic rotating control table arranged outside the cabin body; the rotating table is embedded with a high-strength magnet, and the rotating table is driven to rotate through magnetic coupling by a rotating magnetic field; a gas environment adjusting system including a vacuum pump and a gas cylinder which are connected to the cabin body through a gas pipeline, and which is used for adjusting the air pressure in the cabin body; the rotating table bears an insulator mold, and under the synergistic action of heating and centrifugal rotation, the centrifugal forming and heating solidification of the inner functionally graded material are synchronously completed. The problem that the gradient structure is difficult to accurately maintain due to the two-step process of first centrifugation and then solidification in the preparation of the functionally graded insulator by the existing centrifugal method is solved.

Description

Technical Field

[0001] This invention relates to the field of high-voltage electrical equipment technology, specifically to an integrated centrifugal curing device and method for manufacturing functionally graded material insulators. Background Technology

[0002] Gas-insulated metal-enclosed switchgear (GIS) is a core component of high-voltage power transmission and transformation systems. Insulators, as critical insulating components within GIS, significantly impact the safe and stable operation of substations and power systems. During the manufacturing, installation, operation, and mechanical wear processes of GIS, particulate metal contaminants are easily generated. Under applied voltage, these contaminants adhere to the insulator surface, potentially triggering partial discharge or even insulation breakdown, thus becoming a major cause of GIS insulation failures.

[0003] Existing technologies often employ particle traps as a passive means of capturing metal particles, which suffers from the problem of particles easily escaping from the traps. Furthermore, traps often placed near insulators can distort the surrounding electric field, weakening the insulator's insulation performance. In contrast, Functionally Graded Materials (FGM) insulators, by controlling the spatial distribution of the dielectric constant, achieve homogenization of the surface electric field and actively drive metal particles away from the insulator. This approach achieves dual control over the electric field and particles at the material level, becoming an ideal technical path for solving GIS insulation problems. Among the many methods for preparing FGM insulators, the centrifugal method has attracted much attention due to its relatively mature process, ability to form a gradient structure with continuously varying dielectric constants, and ease of large-scale industrial production. This technology uses centrifugal force generated by rotation to drive fillers with different densities and dielectric constants to migrate directionally in a liquid matrix resin, thereby establishing a controllable dielectric gradient within the material.

[0004] Currently, the existing centrifugal method for preparing functionally graded insulators generally employs a two-step process: centrifugation followed by curing. First, the mixed resin composite liquid is injected into a mold, degassed under vacuum, and then placed in a centrifuge for high-speed rotation. After the filler migrates and forms the desired gradient distribution, the entire mold is removed from the centrifuge and transferred to an oven or curing furnace for heat curing. During this transfer process, due to the removal of centrifugal force, the filler concentration gradient already formed in the uncured resin matrix will diffuse, settle, or even become disordered due to gravity, convection, or Brownian motion, resulting in a blurred final gradient structure and a significant deviation from the design expectations. This phenomenon of gradient layer mixing weakens the accuracy and effectiveness of the centrifugal method, making it difficult for the prepared functionally graded insulators to achieve an ideal dielectric constant distribution, thus affecting their electric field control capability and insulation performance.

[0005] Therefore, no effective solution has yet been proposed to address the problem of difficulty in accurately maintaining the gradient structure in the existing centrifugation method for preparing functionally graded insulators, which is caused by the two-step process of centrifugation followed by curing. Summary of the Invention

[0006] The invention provides an integrated centrifugal curing device and method for manufacturing functionally graded material insulators, which at least solves the problem that the gradient structure is difficult to maintain accurately in the existing centrifugal method for preparing functionally graded insulators due to the two-step process of centrifugation followed by curing.

[0007] According to one aspect of the present invention, a centrifugal curing apparatus for manufacturing functionally graded material insulators is provided, comprising:

[0008] A sealed heating chamber includes a chamber body, a heat-insulating outer shell, and a heat-insulating heating layer laid on the inner wall of the heat-insulating outer shell, for providing a heating environment;

[0009] A magnetically coupled centrifugal drive system includes a rotating platform disposed inside the chamber and a magnetically rotating control console disposed outside the chamber; the rotating platform is embedded with a high-strength magnet, and the magnetically rotating control console generates a rotating magnetic field and magnetically couples with the high-strength magnet to drive the rotating platform to rotate in a non-contact manner.

[0010] A gas environment control system includes a vacuum pump and at least one gas cylinder; the vacuum pump and the gas cylinder are connected to the chamber via gas pipelines and are used to regulate the gas pressure and atmosphere inside the chamber.

[0011] The rotating table supports the insulator mold, so that, under the synergy of the heating effect of the heat insulation layer and the centrifugal rotation effect of the magnetically coupled centrifugal drive system, the centrifugal forming and heating curing of the functional gradient material in the insulator mold are completed simultaneously.

[0012] As an optional solution, a hatch is provided on one side of the cabin, and the hatch is fitted with a heat-insulated transparent observation window; the hatch and the cabin are sealed together by a sealing ring.

[0013] As an alternative, the heat insulation and heating layer is a layered structure composed of heat insulation material and heater.

[0014] As an optional solution, a temperature sensor and a heating controller are also included; the temperature sensor is installed on the inner wall of the cabin, and the temperature sensor is connected to the insulation and heating layer via a wire to the heating controller, which is used to adjust the heating power of the insulation and heating layer according to the temperature feedback from the temperature sensor.

[0015] As an optional solution, a rotary table support is provided below the rotary table; a bearing is fixed at the center of the rotary table support, and an annular groove is provided on the outer edge; a ball bearing is built into the annular groove; the rotary table cooperates with the rotary table support through the bearing and the ball bearing to achieve fixed-axis rotation.

[0016] As an optional solution, the rotating platform is provided with a positioning groove; the insulator mold is provided with a positioning key that matches the positioning groove, so as to realize that the insulator mold and the rotating platform are coaxial and rotate synchronously.

[0017] As an optional solution, the high-strength magnets include multiple magnets, which are evenly arranged along the circumference of the rotary table, and the magnetic poles are arranged in an alternating N-S pattern.

[0018] As an optional solution, the gas environment conditioning system further includes:

[0019] The vacuum valve includes a first vacuum valve connected to the chamber and a second vacuum valve installed in the gas pipeline; the first vacuum valve is used to seal the gas inside the chamber; the second vacuum valve is used to control the opening and closing of the gas pipeline.

[0020] A pressure gauge, connected to the air pipeline, is used to monitor the air pressure inside the cabin.

[0021] According to another aspect of the present invention, a method for manufacturing functionally graded material insulators is also provided, applied to a centrifugal curing integrated apparatus for manufacturing functionally graded material insulators, comprising:

[0022] The mixture containing epoxy resin, curing agent and functional filler is poured into the insulator mold and the insulator mold is placed on a rotating table;

[0023] Close the sealed heating chamber door, start the vacuum pump to create a vacuum environment inside the chamber, close the vacuum pump and vacuum valve, and perform degassing to remove air bubbles from the mixture.

[0024] After the degassing process is completed, the gas environment conditioning system is used to fill the sealed heating chamber with protective gas to the preset pressure.

[0025] Start the magnetic rotation control console, drive the rotary table to rotate the insulator mold at a preset centrifugal speed, so that the functional filler forms a preset gradient distribution under the action of centrifugal force, and while keeping the rotary table rotating at a constant speed, start the heat preservation heating layer, heat and solidify the insulator mold according to the preset temperature curve, and complete the solidification and shaping.

[0026] After curing, turn off the heat insulation layer and allow it to cool naturally to room temperature. Then, turn off the magnetic rotation control console and demold to obtain the functionally graded material insulator.

[0027] As an optional approach, the preparation of the mixture includes:

[0028] In a mixing container, epoxy resin, curing agent, and functional filler are mixed in proportion.

[0029] The mixing container is placed in a water bath and heated and stirred at a first preset temperature to obtain a heated mixture.

[0030] The heated mixture is cooled naturally to room temperature to obtain the final mixture.

[0031] As an optional solution, before pouring the mixture containing epoxy resin, curing agent, and functional filler into the insulator mold, the method further includes:

[0032] The untreated insulator mold and the inner and outer flanges of the insulator were cleaned with anhydrous ethanol and then dried after cleaning; the untreated insulator mold includes an upper mold and a lower mold.

[0033] Assemble the dried inner and outer flanges of the insulator with the insulator mold;

[0034] After assembly, a release agent is sprayed onto the inner walls of the upper and lower molds respectively;

[0035] After the spraying is completed, the upper and lower molds are bolted together and tightened to obtain the insulator mold.

[0036] As an optional solution, the magnetic rotary control console controls the centrifugal rotation of the rotary table, and the preset centrifugal speed setting includes at least one of the following rules:

[0037] Based on the zoning rules for the critical migration speed of functional fillers, the net centrifugal force on functional fillers with a density lower than that of the resin matrix is ​​directed towards the center of rotation to migrate towards the inner diameter, while the net centrifugal force on functional fillers with a density higher than that of the resin matrix is ​​directed away from the center of rotation to migrate towards the outer diameter. The lower limit of the centrifugal speed is determined by the functional filler with high migration resistance, and the upper limit is determined by the viscosity of the resin matrix and the dispersion uniformity of the functional filler.

[0038] Based on the scaling rule of the radial dimension of the insulator, under the condition of maintaining the same centrifugal acceleration, the centrifugal rotation speed is inversely proportional to the square root of the characteristic radius of the insulator;

[0039] Based on the optimization rule of the target gradient magnitude, within the preset centrifugal speed range, high speed corresponds to a large dielectric constant gradient magnitude and a narrow transition region, while low speed corresponds to a small dielectric constant gradient magnitude and a wide transition region.

[0040] As an optional approach, the scaling rule based on the radial dimension of the insulator includes:

[0041] If the radial radius of the insulator is 40mm, then the preset centrifugal speed range is set to 220~900r / min;

[0042] If the radial radius of the insulator is 100mm, then the preset centrifugal speed range is set to 140~560r / min;

[0043] If the radial radius of the insulator is 200mm, the preset centrifugal speed range is set to 100~400r / min.

[0044] As an optional solution, the functional filler includes:

[0045] Lightweight high dielectric constant filler with a density lower than that of a resin matrix; the lightweight high dielectric constant filler includes barium titanate-coated hollow glass microspheres;

[0046] A heavy, low-dielectric-constant filler with a density higher than that of a resin matrix; the heavy, low-dielectric-constant filler includes at least one of alumina and titanium dioxide.

[0047] As an optional approach, the preset temperature profile for heat curing includes curing at a constant temperature of 130°C for 8 hours.

[0048] As an optional solution, during the natural cooling process,

[0049] When the temperature inside the chamber is higher than the glass transition temperature of the resin system, the rotating table is kept rotating at a speed lower than the preset centrifugal speed; the speed range of the speed lower than the preset centrifugal speed is 100~300 r / min;

[0050] The rotation of the rotating platform should be stopped when the temperature inside the chamber is not higher than the glass transition temperature of the resin system.

[0051] The beneficial effects of this invention are as follows:

[0052] 1. This invention integrates a sealed heating chamber, a magnetically coupled centrifugal drive system, and a gas environment control system, enabling continuous, synchronous, and uninterrupted centrifugal molding and heating curing processes. This solves the problem of maintaining the gradient structure precisely due to mold transfer and removal of centrifugal force in traditional two-step processes involving centrifugation followed by curing. The non-contact magnetic drive ensures stable rotation, and the heat-insulating heating layer creates a stable, continuous, and controllable radial gradient distribution of the functional filler in the centrifugal force field. Combined with vacuum and protective atmosphere conditions, it eliminates bubbles and oxidation. Furthermore, the equipment's temperature, rotation speed, and gas pressure parameters are adjustable, making it highly adaptable to various processes and providing reliable structural support for the fabrication of high-precision functionally graded insulators.

[0053] 2. This invention implements a synchronous centrifugation and curing process using an integrated device. By directly initiating heating and curing while maintaining uniform rotation, it completely eliminates the filler diffusion and structural distortion caused by the loss of centrifugal constraint during the time difference between the end of centrifugation and the start of curing in traditional processes, achieving high-fidelity locking of the functional graded material. Through the integration and synchronization of the process flow, the fidelity of the dielectric constant inside the insulator is significantly improved, thereby ensuring the structural consistency and electrical performance reliability of the final insulator product, and facilitating high-efficiency, standardized, and repeatable large-scale production. Simultaneously, by combining an intelligent cooling and speed control strategy based on the glass transition temperature and rotation speed partitioning and scaling rules tailored to the characteristics of the functional filler, it not only effectively avoids the generation of thermal stress cracks but also flexibly adjusts the dielectric constant gradient amplitude, ultimately producing functional graded material insulators with both excellent electrical performance and light mechanical strength. Attached Figure Description

[0054] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other embodiments based on these drawings without creative effort.

[0055] Figure 1 This is a schematic diagram of the device structure according to an embodiment of the present invention.

[0056] Figure 2 This is a simplified schematic diagram of the device structure according to an embodiment of the present invention.

[0057] Figure 3 This is a top view schematic diagram of the connection between the rotary table and the rotary table support according to an embodiment of the present invention.

[0058] Figure 4 This is a side view schematic diagram of the connection between the rotary table and the rotary table support according to an embodiment of the present invention.

[0059] Figure 5 This is a flowchart of an embodiment of the present invention.

[0060] The labels in the above figures are as follows:

[0061] 11. Cabin; 12. Insulated outer shell; 13. Thermal insulation and heating layer; 14. Temperature sensor; 15. Heating controller; 16. Wire; 21. Rotary table; 22. Magnetic rotary control console; 23. Rotary table support; 24. Bearing; 25. Ball bearing; 26. High-strength magnet; 31. Vacuum pump; 32. Gas cylinder; 33. Gas pipeline; 34. Vacuum valve; 35. Pressure gauge; 4. Insulator mold. Detailed Implementation

[0062] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0063] Example 1

[0064] Figure 1 and Figure 2 The device shown is an integrated centrifugal curing apparatus for manufacturing functionally graded insulators. It includes a sealed heating chamber, a magnetically coupled centrifugal drive system, and a gas environment control system. By integrating these components, the centrifugal molding and curing processes are conducted continuously, synchronously, and without interruption. This solves the problem of difficulty in accurately maintaining the structure caused by gradient diffusion, sedimentation, and disorder due to mold transfer and removal of centrifugal force in the traditional two-step process of centrifugation followed by curing. The non-contact magnetic drive ensures stable rotation, and the heat-insulating heating layer 13 forms a stable, continuous, and controllable radial gradient distribution of the functional filler in the centrifugal force field. Combined with a vacuum and protective atmosphere environment, air bubbles and oxidation are eliminated. Furthermore, the equipment's temperature, rotation speed, and gas pressure parameters are adjustable, making it highly adaptable to the process and providing reliable structural support for the preparation of high-precision functionally graded insulators.

[0065] Specifically, the sealed heating chamber includes a chamber body 11, an insulated outer shell 12, and an insulation and heating layer 13 laid on the inner wall of the insulated outer shell 12, for providing a controllable heating environment.

[0066] The cabin 11 has a cubic structure. A hatch is located on one side of the cabin 11, and the hatch is fitted with a heat-insulated transparent observation window. The hatch is sealed to the cabin 11 by a sealing ring to ensure the airtightness of the cabin 11.

[0067] The heat-insulating outer shell 12 is used to support the cabin 11 and to ensure the airtightness of the cabin 11;

[0068] The heat insulation and heating layer 13 is a layered structure composed of heat insulation material and heater, which is used to achieve uniform heating inside the cabin 11.

[0069] The inner wall of the cabin 11 is equipped with a temperature sensor 14, and the temperature sensor 14 is connected to the heater of the insulation and heating layer 13 through a wire 16 to a heating controller 15 for measuring the temperature inside the cabin 11 and adjusting the heating power of the insulation and heating layer 13 according to the feedback temperature inside the cabin 11.

[0070] In this embodiment, the heating controller 15 is equipped with a digital controller for displaying and precisely controlling the temperature inside the cabin 11.

[0071] Specifically, the magnetically coupled centrifugal drive system includes a rotary table 21 disposed inside the cabin 11 and a magnetically rotating control console 22 disposed outside the cabin 11.

[0072] The rotating platform 21 is supported by a rotating platform bracket 23, which is bolted to the center of the heat-insulating outer shell 12 below the sealed heating chamber. A bearing 24 is fixed to the center of the rotating platform bracket 23 via a central hole, and an annular groove is provided along its outer edge. Ball bearings 25 are embedded in the annular groove to transmit mechanical pressure and reduce rotational friction during the rotation of the rotating platform 21. The rotating platform 21, through the cooperation of the bearing 24 and the ball bearings 25 with the rotating platform bracket 23, achieves fixed-axis rotation.

[0073] The rotating table 21 is provided with a positioning groove; the insulator mold 4 is provided with a positioning key that matches the positioning groove, so as to realize that the insulator mold 4 and the rotating table 21 are coaxial and rotate synchronously.

[0074] In this embodiment, the positioning groove includes a cross-shaped, a straight, and a spline-shaped groove. Figure 3 The diagram shown is a top view of the connection between the rotary table 21 and the rotary table support 23. Figure 3 As can be seen, the positioning groove is cross-shaped.

[0075] The rotating stage 21 is embedded with a high-strength magnet 26, which enables the magnetic rotation control console 22 to generate a rotating magnetic field and magnetically couple with the high-strength magnet 26, driving the rotating stage 21 to rotate in a non-contact manner. This allows the insulator mold 4 to maintain continuous centrifugal rotation during the heating and curing process, thereby continuously applying centrifugal force throughout the entire process of functional filler gradient construction and shaping. This effectively suppresses the diffusion, sedimentation, and disorder of functional filler gradient caused by the removal of centrifugal force in the traditional two-step process of centrifugation followed by curing, significantly improving the accuracy of dielectric constant distribution and the clarity of gradient structure. At the same time, the magnetic coupling method transforms dynamic sealing into static sealing, ensuring the complete sealing of the chamber 11 under high vacuum, specific atmosphere, and high temperature conditions. This not only meets the requirements of high cleanliness preparation but also avoids the wear and aging problems of traditional dynamic seals at high temperatures. Figure 4 The diagram shown is a side view of the connection between the rotary table 21 and the rotary table support 23.

[0076] In this embodiment, the magnetic rotation control console 22 has a built-in coil for generating a rotating magnetic field when energized.

[0077] In this embodiment, the magnetic rotary control console 22 is equipped with a speed control knob for controlling the rotational speed of the rotary table 21.

[0078] In this embodiment, there are multiple high-strength magnets 26, which are evenly arranged along the circumference of the rotating platform 21, and the magnetic poles are arranged in an alternating N-S pattern and embedded in the groove at the bottom of the rotating platform 21.

[0079] In this embodiment, the groove at the bottom of the rotary table 21 is covered with a non-magnetic material.

[0080] Specifically, the gas environment control system includes a vacuum pump 31, at least one gas cylinder 32, a vacuum valve 34, and a pressure gauge 35. Through the opening and closing of the vacuum valve 34, the system can achieve precise control of different gas environments inside the sealed heating chamber.

[0081] The vacuum pump 31 and the gas cylinder 32 are connected to the chamber 11 through the gas pipeline 33, which are used to regulate the gas pressure and atmosphere inside the chamber 11.

[0082] The vacuum valve 34 includes a first vacuum valve and a second vacuum valve; the first vacuum valve is connected to the chamber 11 and is used to seal the gas inside the chamber 11; the second vacuum valve is installed in the gas pipeline 33 and is used to control the opening and closing of the gas pipeline 33.

[0083] In this embodiment, there are multiple second vacuum valves, which are arranged in a one-to-one correspondence with the gas pipelines 33.

[0084] Among them, the pressure gauge 35 is connected to the gas pipeline 33 and is used to monitor the air pressure inside the chamber 11, as well as to flexibly adjust the ratio control of the mixed gas environment inside the chamber 11. It can meet the preparation requirements of different substrates and curing processes, and has good process adaptability and scientific research value.

[0085] In this embodiment, if a tee connection is made in the gas pipeline 33, it is possible to further expand the system by connecting multiple gas cylinders 32 in parallel.

[0086] In this embodiment, the rotary table 21 carries the insulator mold 4 so that, under the combined effect of the heating effect of the heat insulation heating layer 13 and the centrifugal rotation effect of the magnetic coupling centrifugal drive system, the centrifugal forming and heating curing of the functional gradient material in the insulator mold 4 are completed simultaneously.

[0087] Example 2

[0088] Based on the same design concept, this embodiment provides a method for manufacturing functionally graded material insulators, applied to a centrifugal curing integrated equipment for manufacturing functionally graded material insulators, including:

[0089] Step S100: The mixture containing epoxy resin, curing agent and functional filler is poured into the insulator mold 4 and the insulator mold 4 is placed on the rotating table 21.

[0090] Step S200: Close the sealed heating chamber door, start the vacuum pump 31 to evacuate the inside of the chamber 11 to form a vacuum environment, close the vacuum pump 31 and vacuum valve 34, and perform degassing to remove air bubbles from the mixture.

[0091] Step S300: After the degassing process is completed, protective gas is introduced into the sealed heating chamber to the preset pressure using the gas environment conditioning system.

[0092] Step S400: Start the magnetic rotation control console 22, drive the rotating table 21 to rotate the insulator mold 4 at a preset centrifugal speed for a preset centrifugal time, so that the functional filler forms a preset gradient distribution under the action of centrifugal force, and while keeping the rotating table 21 rotating at a uniform speed, start the heat preservation heating layer 13, and heat and solidify the insulator mold 4 according to the preset temperature curve to complete the solidification and shaping.

[0093] Step S500: After curing, turn off the heat insulation layer 13, allow it to cool naturally to room temperature, then turn off the magnetic rotation control console 22, and demold to obtain the functionally graded material insulator.

[0094] Based on the integrated centrifugal curing equipment for manufacturing functionally graded material insulators, a synchronous centrifugation and curing process is implemented. By directly initiating heating and curing while maintaining uniform rotation, the filler diffusion and structural distortion caused by the loss of centrifugal constraint during the time difference between the end of centrifugation and the start of curing, as in traditional processes, are completely eliminated, achieving high-fidelity locking of the functional grade. Through the integration and synchronization of the process flow, the fidelity of the dielectric constant inside the insulator is significantly improved, thereby ensuring the structural consistency and electrical performance reliability of the final insulator product. In addition, the integrated design of centrifugation and curing eliminates the intermediate step of transferring the insulator mold 4 between different devices, simplifying the operation process, shortening the preparation cycle, and eliminating process deviations caused by batch-to-batch differences in transfer operations, which is conducive to achieving high-efficiency, standardized, and repeatable large-scale production.

[0095] Please see Figure 5 , Figure 5 This is an optional flowchart of a method for manufacturing functionally graded material insulators provided in an embodiment of this application. In some embodiments of this application, Figure 5The method described below may include, but is not limited to, steps S100 to S500. Figure 5 The specific implementation of each step is explained in detail.

[0096] Specifically, before step S100, it is necessary to prepare the mixture and pre-treat the insulator mold 4.

[0097] The preparation of the mixture provides a material basis for achieving electric field homogenization and active particle control. Specifically, it includes: mixing epoxy resin, curing agent, and functional filler in a mixing container in proportion; placing the mixing container in a water bath and heating and stirring at a first preset temperature to obtain a heated mixture; and allowing the heated mixture to cool naturally to room temperature to obtain the final mixture.

[0098] In this embodiment, the functional fillers include lightweight high dielectric constant fillers with a density lower than that of the resin matrix and heavy low dielectric constant fillers with a density higher than that of the resin matrix.

[0099] Specifically, the lightweight, high-dielectric-constant filler includes barium titanate-coated hollow glass microspheres (BaTiO3@HGM), with an equivalent density of 1.2–1.5 g / cm³, close to the density of the epoxy resin matrix (1.15 g / cm³). The dielectric constant can be varied within the range of 5–60 by adjusting the coating thickness. During centrifugation, the lightweight, high-dielectric-constant filler does not settle towards the outer diameter but accumulates locally within the inner diameter, thereby increasing the dielectric constant in high-field regions.

[0100] Specifically, the heavy, low-dielectric-constant filler includes at least one of alumina (Al2O3) and titanium dioxide (TiO2). Alumina (Al2O3) has a density of 3.95 g / cm³ and a dielectric constant of 9–10; titanium dioxide (TiO2), as an auxiliary adjusting filler, has a density of 4.23 g / cm³ and a dielectric constant of 80–110. During centrifugation, because the density of the heavy, low-dielectric-constant filler is higher than that of the resin matrix, it migrates outwards, forming a low-dielectric-constant layer on the outer diameter side.

[0101] In this embodiment, the total mass of the functional fillers is based on the mass of the epoxy resin. The amount of barium titanate-coated hollow glass microspheres is 5% to 20% of the epoxy resin mass, preferably 8% to 15%; the amount of alumina (Al2O3) is 50% to 120% of the epoxy resin mass, preferably 60% to 100%; and the amount of titanium dioxide (TiO2) is 10% to 30% of the epoxy resin mass, preferably 15% to 25%. The amount of curing agent is 5% to 8% of the epoxy resin mass.

[0102] In this embodiment, the first preset temperature is 40°C.

[0103] The pretreatment of the insulator mold 4 specifically includes: cleaning the untreated insulator mold 4 and the inner and outer flanges of the insulator with anhydrous ethanol, and drying them after cleaning; the untreated insulator mold 4 includes an upper mold and a lower mold; assembling the dried inner and outer flanges of the insulator with the insulator mold 4; after assembly, spraying a release agent on the inner walls of the upper mold and the lower mold respectively; after spraying, bolting the upper mold and the lower mold together and tightening them to obtain the insulator mold 4.

[0104] Specifically, in step S200, the door of the sealed heating chamber is closed, the vacuum pump 31 is started to evacuate the interior of the chamber 11 to form a vacuum environment, the vacuum pump 31 and the vacuum valve 34 are closed, and degassing is performed to remove air bubbles from the mixture. This includes: closing the door of the heating chamber, starting the vacuum pump 31 to evacuate the interior of the chamber 11 to form a vacuum environment; after the vacuum environment is formed, closing the vacuum valve 34 and the vacuum pump 31, and starting the timing to perform degassing to remove air bubbles from the mixture.

[0105] In this embodiment, a vacuum environment is defined as an air pressure inside chamber 11 of less than 0.002 MPa; and a degassing time of 1 hour.

[0106] Specifically, in step S300, the protective gas pressure includes nitrogen. The preset pressure of the protective gas pressure is 0.1 MPa.

[0107] Specifically, in step S400, the magnetic rotation control console 22 controls the centrifugal rotation of the rotary table 21, and the preset centrifugal speed includes at least one of the following rules:

[0108] (1) Based on the zoning rules of the critical migration speed of functional fillers, the net centrifugal force on functional fillers with a density lower than that of the resin matrix is ​​directed toward the rotation center to migrate toward the inner diameter, and the net centrifugal force on functional fillers with a density higher than that of the resin matrix is ​​directed away from the rotation center to migrate toward the outer diameter; the lower limit of the centrifugal speed is determined by the functional filler with a large migration resistance, and the upper limit is determined by the viscosity of the resin matrix and the dispersion uniformity of the functional filler.

[0109] In this embodiment, the migration rate is positively correlated with the centrifugal acceleration.

[0110] In this embodiment, based on rule (1), the preset centrifugation speed range is set to 800-2000 r / min, and the preset centrifugation time is 30-60 minutes.

[0111] (2) Based on the scaling rule of the radial dimension of the insulator, under the condition of maintaining the same centrifugal acceleration, the centrifugal speed is inversely proportional to the square root of the characteristic radius of the insulator.

[0112] Preferably, the scaling rules based on the radial dimensions of the insulator include:

[0113] If the radial radius of the insulator is 40mm, the preset centrifugal speed range is set to 220~900r / min;

[0114] If the radial radius of the insulator is 100mm, the preset centrifugal speed range is set to 140~560r / min;

[0115] If the radial radius of the insulator is 200mm, the preset centrifugal speed range is set to 100~400r / min.

[0116] (3) Based on the optimization rule of the target gradient magnitude, within the preset centrifugal speed range, high speed corresponds to a large dielectric constant gradient magnitude and a narrow transition region, while low speed corresponds to a small dielectric constant gradient magnitude and a wide transition region.

[0117] Specifically, at high speeds, the centrifugal force on the functional filler increases, accelerating the enrichment of lightweight, high-dielectric-constant filler towards the inner diameter and the migration of heavy, low-dielectric-constant filler towards the outer diameter. The resulting gradient structure exhibits a higher dielectric constant on the inner diameter side and a lower dielectric constant on the outer diameter side, with a narrower transition zone, i.e., a larger dielectric constant gradient amplitude. This is suitable for scenarios with high requirements for electric field homogenization and large pressure differences between the inner and outer diameters of the insulator. At low speeds, the migration speed of the functional filler decreases, and the concentration changes more slowly within the same centrifugation time, resulting in a gentler dielectric constant gradient and a wider transition zone, i.e., a smaller dielectric constant gradient amplitude. This is suitable for scenarios with high requirements for mechanical internal stress control or where only fine-tuning of the electric field distribution is needed.

[0118] It should be noted that in actual use, the above rules (1) to (3) are not mutually exclusive, but can be used in combination to accurately set the preset centrifugal speed. Specifically, the following rules can be followed in the setting process: First, determine the basic centrifugal speed range that meets the migration dynamics of the functional filler according to rule (1); second, combine rule (2) to make adaptability correction to the basic centrifugal speed range according to the radial dimensions of the insulator mold 4; finally, according to the specific requirements of rule (3) for the target gradient amplitude, select the final centrifugal speed within the corrected centrifugal speed range. By setting multiple rules in a coordinated manner, material characteristics, product size and performance indicators are taken into account, and high-precision gradient structure preparation is achieved.

[0119] In this embodiment, the preset temperature curve for heat curing includes curing at a constant temperature of 130°C for 8 hours.

[0120] In this embodiment, during the natural cooling process, when the temperature inside the chamber 11 is higher than the glass transition temperature of the resin system, the rotating table 21 is kept rotating at a speed lower than the preset centrifugal speed to suppress secondary migration that may be caused by thermal convection during the cooling stage; the speed range below the preset centrifugal speed is 100~300 r / min; when the temperature inside the chamber 11 is not higher than the glass transition temperature of the resin system, the rotating table 21 is stopped rotating.

[0121] In this embodiment, the cooling process takes 2 to 4 hours.

[0122] Preferably, for applications requiring high precision of the gradient structure, i.e., the dielectric constant deviation at any radial position is within ±5%, the rotary table 21 is maintained at low speed centrifugal rotation throughout the natural cooling process; for applications with general gradient structure precision, the rotary table 21 is stopped rotating after the temperature inside the chamber 11 drops to the glass transition temperature.

[0123] In this embodiment, the glass transition temperature range of the epoxy resin system is 130~150℃, and the curing temperature is 130℃. During the natural cooling process, when the temperature inside the chamber 11 drops from 130℃ to 100℃, the centrifugal speed of the rotating table 21 is maintained at 150 r / min; after the temperature inside the chamber 11 drops below 100℃, the resin matrix fully enters the glassy state, the rotation of the rotating table 21 is stopped, and the system is allowed to cool naturally to room temperature.

[0124] It should be noted that for any resin system, the glass transition temperature of its cured product can be obtained by differential scanning calorimetry (DSC) or dynamic thermomechanical analysis (DMA), and this can be used as a criterion for determining whether the centrifugal rotation of the rotating stage 21 is maintained during the natural cooling process.

[0125] Example 3

[0126] In this embodiment, a preferred embodiment of a method for manufacturing functionally graded material insulators is provided, using a scaled-down pot-shaped insulator model with an inner diameter of 16 mm, an outer diameter of 94 mm, and a height of 34 mm. Specifically, the method includes the following steps:

[0127] T1: Preparation of the mixture;

[0128] T11: In a mixing container, epoxy resin, curing agent and functional filler are mixed in proportion;

[0129] T12: Place the mixing container in a water bath and heat and stir at 40°C for 1 hour to obtain a heated mixture;

[0130] T13: After the heated mixture is allowed to cool naturally to room temperature, the mixture is obtained;

[0131] T2: Pre-treatment of insulator mold 4;

[0132] T21: Based on the untreated insulator mold 4 and the inner and outer flanges of the insulator, anhydrous ethanol is used for cleaning, and after cleaning, it is dried; the untreated insulator mold 4 includes an upper mold and a lower mold.

[0133] T22: Assemble the dried inner and outer flanges of the insulator with the insulator mold 4;

[0134] T23: After assembly, spray release agent onto the inner walls of the upper and lower molds respectively;

[0135] T24: After the spraying is completed, the upper mold and the lower mold are connected by bolts and tightened to obtain insulator mold 4.

[0136] T3: Pour the mixture containing epoxy resin, curing agent and functional filler into the insulator mold 4, and place the insulator mold 4 on the rotating table 21;

[0137] T4: Close the sealed heating chamber door, start the vacuum pump 31 to evacuate the inside of the chamber 11, and form a vacuum environment after the air pressure inside the chamber 11 drops to 0.002MPa. Then close the vacuum pump 31 and vacuum valve 34, and degas for 1 hour to remove air bubbles from the mixture.

[0138] T5: After the degassing process is completed, nitrogen gas is introduced into the sealed heating chamber to a pressure of 0.1 MPa using the gas environment conditioning system;

[0139] T6: Start the magnetic rotation control console 22, drive the rotary table 21 to rotate the insulator mold 4 at a centrifugal speed of 800~2000 r / min for 30-60 min, so that the functional filler forms a preset gradient distribution under the action of centrifugal force, and while keeping the rotary table 21 rotating at a uniform speed, start the heat preservation heating layer 13, and heat and solidify the insulator mold 4 according to the preset temperature curve to complete the solidification and shaping.

[0140] In this embodiment, the preset temperature curve for heat curing includes curing at a constant temperature of 130°C for 8 hours.

[0141] T7: After curing, turn off the heat insulation layer 13 and allow it to cool naturally to room temperature;

[0142] T71: When the temperature inside chamber 11 drops from 130℃ to 100℃, the centrifugal speed of rotating table 21 is maintained at 150r / min;

[0143] T72: When the temperature inside the cabin 11 drops below 100°C, the magnetic rotation control console 22 is turned off, and the cabin continues to cool naturally to room temperature before demolding to obtain a functionally graded material insulator.

[0144] It should be noted that the term "comprising" and its variations used in the embodiments of this invention are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "a plurality" mentioned in the embodiments of this invention are illustrative and not restrictive, and those skilled in the art should understand that unless explicitly indicated otherwise in the context, they should be understood as "one or more".

[0145] The user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in the embodiments of this invention are subject to strict compliance with relevant laws, regulations, and regulatory requirements in their collection, storage, use, processing, transmission, provision, and disclosure, and adhere to the principles of legality, legitimacy, necessity, and good faith. The acquisition of relevant information and data is premised on the user's explicit consent or other legitimate reasons, and a clear and convenient authorization management approach is provided to the user, allowing the user to independently choose to consent, withdraw consent, or refuse to provide relevant information. For functions that rely on user information, if the user does not authorize or withdraws authorization, the corresponding technical function cannot be implemented, and the technical solution of this invention is not applicable in this scenario. The steps described in the method implementation embodiments provided by the embodiments of this invention can be executed in different orders and / or in parallel. Furthermore, the method implementation embodiments may include additional steps and / or omit the steps shown. The scope of protection of this invention is not limited in this respect.

[0146] The term "embodiment" in this specification refers to a specific feature, structure, or characteristic described in connection with an embodiment that may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily imply the same embodiment, nor does it imply independence or alternativeity from other embodiments. The various embodiments in this specification are described in a related manner, with reference to each other for similar or identical parts. In particular, for apparatus, device, and system embodiments, since they are substantially similar to method embodiments, the description is relatively simple, and relevant details are referred to in the description of the method embodiments.

[0147] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of protection. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A centrifugal curing integrated device for manufacturing functionally graded material insulators, characterized in that, include: The sealed heating chamber includes a chamber body (11), a heat-insulating shell (12), and a heat-insulating heating layer (13) laid on the inner wall of the heat-insulating shell (12) for providing a heating environment; The magnetically coupled centrifugal drive system includes a rotating platform (21) disposed inside the cabin (11) and a magnetically rotating control console (22) disposed outside the cabin (11); the rotating platform (21) is embedded with a high-strength magnet (26), and the magnetically rotating control console (22) drives the rotating platform (21) to rotate in a non-contact manner by generating a rotating magnetic field and magnetically coupling with the high-strength magnet (26); A gas environment conditioning system includes a vacuum pump (31) and at least one gas cylinder (32); the vacuum pump (31) and the gas cylinder (32) are connected to the chamber (11) through a gas pipeline (33) for regulating the gas pressure and atmosphere inside the chamber (11); The rotating table (21) carries the insulator mold (4) so ​​that, under the combined action of the heating effect of the heat insulation layer (13) and the centrifugal rotation effect of the magnetic coupling centrifugal drive system, the centrifugal forming and heating curing of the functional gradient material in the insulator mold (4) can be completed simultaneously.

2. The centrifugal curing integrated equipment for manufacturing functionally graded material insulators according to claim 1, characterized in that, The cabin (11) has a door on one side, and the door is fitted with a heat-insulated transparent observation window; the door and the cabin (11) are sealed together by a sealing ring.

3. The centrifugal curing integrated equipment for manufacturing functionally graded material insulators according to claim 1, characterized in that, The heat insulation and heating layer (13) is a layered structure composed of heat insulation material and heater.

4. The centrifugal curing integrated equipment for manufacturing functionally graded material insulators according to claim 3, characterized in that, It also includes a temperature sensor (14) and a heating controller (15); the temperature sensor (14) is installed on the inner wall of the cabin (11), and the temperature sensor (14) and the heat insulation and heating layer (13) are connected to the heating controller (15) through a wire (16) to adjust the heating power of the heat insulation and heating layer (13) according to the temperature feedback from the temperature sensor (14).

5. The centrifugal curing integrated equipment for manufacturing functionally graded material insulators according to claim 4, characterized in that, The rotary table (21) is provided with a rotary table support (23) below it; a bearing (24) is fixed in the center of the rotary table support (23), and an annular groove is provided on the outer edge; a ball bearing (25) is built into the annular groove; the rotary table (21) cooperates with the rotary table support (23) through the bearing (24) and the ball bearing (25) to achieve fixed-axis rotation.

6. The centrifugal curing integrated equipment for manufacturing functionally graded material insulators according to claim 5, characterized in that, The rotating table (21) is provided with a positioning groove; the insulator mold (4) is provided with a positioning key that matches the positioning groove, so as to realize that the insulator mold (4) and the rotating table (21) are coaxial and rotate synchronously.

7. The centrifugal curing integrated equipment for manufacturing functionally graded material insulators according to claim 1, characterized in that, The high-strength magnets (26) include a plurality of high-strength magnets (26) which are evenly arranged along the circumference of the rotating platform (21) and the magnetic poles are arranged in an alternating N-S arrangement.

8. The centrifugal curing integrated equipment for manufacturing functionally graded material insulators according to claim 1, characterized in that, The gas environment control system further includes: The vacuum valve (34) includes a first vacuum valve connected to the cabin (11) and a second vacuum valve installed in the gas pipeline (33); the first vacuum valve is used to seal the gas inside the cabin (11); the second vacuum valve is used to control the opening and closing of the gas pipeline (33); A barometer (35) is connected to the air pipeline (33) and is used to monitor the air pressure inside the cabin (11).

9. A method for manufacturing functionally graded material insulators, characterized in that, The centrifugal curing apparatus for manufacturing functionally graded material insulators as described in any one of claims 1 to 8 comprises: The mixture containing epoxy resin, curing agent and functional filler is poured into the insulator mold (4) and the insulator mold (4) is placed on the rotating table (21); Close the sealed heating chamber door, start the vacuum pump (31) to evacuate the inside of the chamber (11) to form a vacuum environment, close the vacuum pump (31) and vacuum valve (34), and perform degassing to remove air bubbles from the mixture; After the degassing process is completed, the gas environment conditioning system is used to fill the sealed heating chamber with protective gas to the preset pressure. Start the magnetic rotation control console (22), drive the rotating table (21) to rotate the insulator mold (4) at a preset centrifugal speed, so that the functional filler forms a preset gradient distribution under the action of centrifugal force, and while keeping the rotating table (21) rotating at a uniform speed, start the heat preservation heating layer (13), and heat and solidify the insulator mold (4) according to the preset temperature curve to complete the solidification and shaping. After curing, the heat insulation layer (13) is turned off, and the temperature is allowed to drop naturally to room temperature. Then, the magnetic rotation control console (22) is turned off, and the functionally graded material insulator is demolded.

10. The method for manufacturing functionally graded material insulators according to claim 9, characterized in that, The preparation of the mixture includes: In a mixing container, epoxy resin, curing agent, and functional filler are mixed in proportion. The mixing container is placed in a water bath and heated and stirred at a first preset temperature to obtain a heated mixture. The heated mixture is cooled naturally to room temperature to obtain the final mixture.

11. The method for manufacturing functionally graded material insulators according to claim 9, characterized in that, Before pouring the mixture containing epoxy resin, curing agent and functional filler into the insulator mold (4), the process further includes: Based on the untreated insulator mold (4) and the inner and outer flanges of the insulator, anhydrous ethanol is used for cleaning, and after cleaning, it is dried; the untreated insulator mold (4) includes an upper mold and a lower mold; The dried inner and outer flanges of the insulator are assembled with the insulator mold (4); After assembly, a release agent is sprayed onto the inner walls of the upper and lower molds respectively; After the spraying is completed, the upper mold and the lower mold are bolted together and tightened to obtain the insulator mold (4).

12. The method for manufacturing functionally graded material insulators according to claim 9, characterized in that, The magnetic rotation control console (22) controls the centrifugal rotation of the rotary table (21), and the preset centrifugal speed setting includes at least one of the following rules: Based on the zoning rules for the critical migration speed of functional fillers, the net centrifugal force on functional fillers with a density lower than that of the resin matrix is ​​directed towards the center of rotation to migrate towards the inner diameter, while the net centrifugal force on functional fillers with a density higher than that of the resin matrix is ​​directed away from the center of rotation to migrate towards the outer diameter. The lower limit of the centrifugal speed is determined by the functional filler with high migration resistance, and the upper limit is determined by the viscosity of the resin matrix and the dispersion uniformity of the functional filler. Based on the scaling rule of the radial dimension of the insulator, under the condition of maintaining the same centrifugal acceleration, the centrifugal rotation speed is inversely proportional to the square root of the characteristic radius of the insulator; Based on the optimization rule of the target gradient magnitude, within the preset centrifugal speed range, high speed corresponds to a large dielectric constant gradient magnitude and a narrow transition region, while low speed corresponds to a small dielectric constant gradient magnitude and a wide transition region.

13. The method for manufacturing functionally graded material insulators according to claim 12, characterized in that, The scaling rules based on the radial dimensions of the insulator include: If the radial radius of the insulator is 40mm, then the preset centrifugal speed range is set to 220~900r / min; If the radial radius of the insulator is 100mm, then the preset centrifugal speed range is set to 140~560r / min; If the radial radius of the insulator is 200mm, the preset centrifugal speed range is set to 100~400r / min.

14. The method for manufacturing functionally graded material insulators according to claim 9, characterized in that, The functional filler includes: Lightweight high dielectric constant filler with a density lower than that of a resin matrix; the lightweight high dielectric constant filler includes barium titanate-coated hollow glass microspheres; A heavy, low-dielectric-constant filler with a density higher than that of a resin matrix; the heavy, low-dielectric-constant filler includes at least one of alumina and titanium dioxide.

15. The method for manufacturing functionally graded material insulators according to claim 9, characterized in that, The preset temperature curve for heat curing includes curing at a constant temperature of 130°C for 8 hours.

16. The method for manufacturing functionally graded material insulators according to claim 9, characterized in that, During the natural cooling process When the temperature inside the chamber (11) is higher than the glass transition temperature of the resin system, the rotating table (21) is kept rotating at a speed lower than the preset centrifugal speed; the speed range of the speed lower than the preset centrifugal speed is 100~300r / min; When the temperature inside the chamber (11) is not higher than the glass transition temperature of the resin system, the rotation of the rotating table (21) is stopped.

Images